What is USB?

USB represents Universal Serial Bus. It is an industry-standard developed in the mid-1990s that represents the cables, connectors, and communication protocols used in a bus for connection, communication, and power supply among computer and electronic devices.

USB operates at 12 Mbps with particular consideration for low-cost peripherals. It provides up to 127 devices with both synchronous and asynchronous data transfers. A USB cable has a rectangular “TYPE A” plug at the computer end and a square “TYPE B” plug at the peripheral end.

A Universal Serial Bus (USB) is a common interface that allows the connection between devices and host controllers including a personal computer (PC). It connects peripheral devices including digital cameras, mice, keyboards, printers, scanners, media devices, external hard drives, and flash drives.

Hot swapping is one of the major advantages of USB, which enables a device to be eliminated from the system without the requirement of rebooting the system. Because previous ports required that a PC be reboot while inserting or deleting a new device with them. By rebooting the system, the device will be reconfigured and can avoid electrostatic discharge.

Advantages of USB

There are various advantages of USB which are as follows −

Single Interface for multiple devices− The versatile feature of USB eliminates the complexity of several connector types and hardware needed for each peripheral.

Compact Size − USB sockets are small in dimensions as compared to RS232 or parallel ports. There is no external power required. The USB interface was established from the first day to double duty as a DC power supply. Several host devices through its USB port can supply 5V DC delivering 500mA (USB 1.0 and 2.0) to 900 mA (USB 3.0) to the peripheral.

Speed − USB offers multiple speed modes which create it more effective and swift compared to RS232 and parallel ports. It provides speed ranges from 1.5Mbit/s to 5Gbit/s. With the introduction of USB 3.1 in 2013, the speed has been raised to 10Gbit/s.

Reliability − The USB protocol can hook errors during data transfer and inform the transmitter to retransmit the information. The generic USB driver and unique driver software provide error-free data communication.

Disadvantages of USB

There are various disadvantages of USB which are as follows −

Peer to Peer Communication − According to the USB standard, the connection takes place between the host and the peripheral. Two hosts cannot connect directly with each other. The same is the case for a peripheral. Similarly, interfaces like FireWire provides peripheral to peripheral communication. For overcoming this drawback, the USB introduced the term OTG (On the Go). The OTG device usually functions as a peripheral, but it can also function as a host with some small capability when needed.

Distance − As per the USB standards, the connecting cable can be seeing 5 meters, further which, USB hubs require to be used for enlarging the connectivity.

Broadcasting − Universal Serial Bus does not support the broadcasting nature, only single messages can be connected between the host and peripheral.